1. Technical Field
The present invention relates to an apparatus and a method for manufacturing a camera module employed in a portable mobile communication device such as a mobile phone, or the like, and more particularly, to an apparatus and method for manufacturing a camera module capable of minimizing a tilt deviation between an image sensor and a lens housing module by making a mounting reference surface of the image sensor and that of the lens housing module the same spot (surface) to thus allow a mounting tilt of the image sensor to be simultaneously changed according to a tilt of a substrate (i.e., a printed circuit board (PCB)) when the lens housing is mounted on the substrate.
2. Description of the Related Art
Recently, the development of technologies of portable terminals such as mobile phones, personal digital assistants (PDAs), and the like, has promoted portable terminals to be used as multi-convergence devices supporting music, movie, TV, games, and the like, beyond the basic simple phone function thereof, and a camera module may be considered one of the most representative elements leading portable terminals toward multi-convergence. Camera modules have shifted from the conventional 300,000 pixel (VGA level) modules to the current high pixel modules based on 8 megapixels or higher, and are moving toward implementation of various additional functions such as autofocusing (AF), optical zoom, and the like.
In general, a compact camera module (CCM) is applied to portable mobile communication devices including a camera phone, a PDA, or a smart phone, and various other IT devices such as a toy camera, or the like. Recently, devices equipped with CCMs have increasingly been launched to meet consumers' diverse preferences.
Such camera modules, fabricated to include an image sensor such as a CCD, a CMOS, or the like, as a key component, concentrate light to form an image of an object through an image sensor, and store the same in a memory of the device. The stored data is displayed as an image through a display medium such as an LCD, a PC monitor, or the like, of the device.
General packaging schemes of an image sensor for a camera module include a flip-chip type chip on film (COF) scheme, a wire bonding type chip on board (COB) scheme, a chip scaled package (CSP) scheme, and the like, and among them, the COF package scheme and the COB package scheme are widely used.
The COB scheme is comprised of a dicing (wafer sawing) process, a die attach (D/A) process, a wire bonding (W/B) process, and a housing attach (H/A) process. Each process will be briefly described as follows.
Dicing process: Image sensors in a bare wafer state are fixedly attached to a tape of a wafer ring, and then, cut into individual unit image sensors by moving a blade made of diamond particles at particular positions of a corresponding pattern in X and Y directions while rotating the blade at a high speed.
D/A process: An epoxy is applied to a PCB, and, upon recognizing an image of the particular position pattern formed on the PCB, the individual unit image sensors severed during the dicing process are repeatedly attached to certain positions and cured.
W/B process: A gold wire is connected to pads of the image sensors and the pattern of the PCB by using a capillary such that they are electrically connected.
H/A process: An epoxy is applied to edges of the PCB with image sensors mounted thereon, and then, a lens-attached housing module is repeatedly attached at a certain position and cured.
Through the foregoing processes, a camera module is fabricated. A high pixel module having 12 megapixels has been developed based on the current technology, but currently, 5-mega pixel module is universally mass produced while a high pixel module having 8 megapixels is at the beginning stage of being mass produced. The existing 5-mega pixel camera module and the 8-megapixel camera module are developed to have the same standard in the overall size of the outer appearance. It is anticipated that the size of modules is reduced while the number of pixels continues to increase.
With the development of high pixel image sensors, the number of pixels of modules has increased during the same period, but a problem of resolving power occurs as the number of pixels is sharply increased. Namely, as shown in FIG. 1(a), ideal resolving power is obtained when a central axis of a lens 140 is 90° with respect to a surface of an image sensor 120 which receives light, and in this case, when the image sensor 120 tilts as shown in FIG. 1(b), resolving power of the entire screen or a particular corner is degraded, resulting in a degradation of resolving power of the entire screen. In FIG. 1, reference numeral 110 denotes a PCB, reference numeral 130 denotes an infrared blocking filter, and reference numeral 150 denotes a lens housing module, respectively.
The tilt of the image sensor degrading resolving power is caused by multiple factors according to flatness of the PCB, how an epoxy is applied (an epoxy application method), how much an epoxy is applied (an application amount of an epoxy), how the image sensor is mounted (a method of mounting the image sensor), a curing method, and the like, when an epoxy is applied to the PCB, the image sensor is mounted on the PCB, and curing is then performed during the D/A process.